"Somebody got in the house and attacked me and my husband,” 94-year-old Harriet Anderson said to emergency dispatch just minutes after she and her husband, Rupert, were attacked.

Police said 19-year-old Ngor Makuey brutally beat the elderly couple with a metal object. Rupert later died at the hospital.

A search warrant obtained by KCCI gives new insight into how detectives caught their suspect so quickly.

The documents indicate Makuey was actually still at the crime scene when help arrived. Officers originally thought he was a family member because he seemed "calm and stayed out of the way as medics entered the home."

“The fact that he was right close to the scene is very, very unusual,” said Sgt. Jason Halifax of the Des Moines Police Department.

Halifax said suspects usually only stick around on crime scenes if they feel what they did was justified.

“This is not only a homicide, this is a murder. It’s not justifiable by any stretch of the imagination,” he said.

The search warrant also explained how officers captured Makuey on video, and later showed his picture around his nearby neighborhood.

Makuey's mother is the one who identified him.

Detectives seized Makuey's bloody sweatshirt and a list of other possible evidence.

“I think in our society right now, defending an immigrant charged with a crime like this comes with a very difficult challenge,” said legal expert Angela Campbell.

Campbell is a defense attorney and said the evidence might seem overwhelming, but public opinion shouldn't rush to convict him.

“What’s important is just to wait and let the process work its way through the justice system as it’s designed to do,” she said.

Police believe Makuey did not steal anything during the alleged crime, leaving officers baffled as to what a possible motive could be.

There is no known connection between the suspect and the victims.

Makuey was supposed to appear for his arraignment in court Monday, but he waived that appearance.